#include<bits/stdc++.h>
#define ll long long
#define ull unsigned long long
using namespace std;

const int N = 5e5 + 10, INF = 0x3f3f3f3f;

int n, m;
string s, t;
int op[N];

void solve()
{
    cin >> n >> m >> s >> t;
    s = " " + s;t = " " + t;
    while (m--) {
        int l, r;cin >> l >> r;
        op[l] ^= 1;op[r + 1] ^= 1;
    }
    int flag = 0;
    for (int i = 1;i <= n;i++) {
        flag ^= op[i];
        if (flag) {
            cout << t[i];
        } else {
            cout << s[i];
        }
    }
}

signed main()
{
    //ios::sync_with_stdio(0);
    //cin.tie(0);cout.tie(0);
#define ONLINE_JUDGE
#ifndef ONLINE_JUDGE
    std::istringstream in(R"()");
    std::cin.rdbuf(in.rdbuf());
#endif
    int T = 1;
    //cin>>T;
    for (int i = 1;i <= T;i++) {
        solve();
    }
}